C4 spark plugs, time involved?
Drifting
Joined: Jul 2007
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One Hour worth of work.
One hour. The two rear plugs on the passenger side are easy to get at from below the car. On the right side, removal of the ASR makes it alot easier. Don't disconnect it, just unbolt it and push it to the side.
Does require patience!
Do it when the engine is completely cool to avoid stripping the threads.
Does require patience!
Do it when the engine is completely cool to avoid stripping the threads.
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Also I find it helpful to stick the tip of the plug into some rubber fuel line to give you a little extra length when trying to start a plug when your hand doesn't quite fit into the area.
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If its your first time doing it, it'll be about 2-2.5 hours...mostly because of the difficulty getting a solid grip on the passenger side. I can do it now in about an hour.
Removing the wheel well liner would be a good idea, but be prepared to curse when getting off #8.
And definitely with the engine cold, and use the anti-seize.
Removing the wheel well liner would be a good idea, but be prepared to curse when getting off #8.
And definitely with the engine cold, and use the anti-seize.
Drifting
Joined: Jul 2007
Posts: 1,294
Likes: 37
I can't see how. Assuming the engine was tuned when the plugs were in good shape......I would imagine that the engine would run better overall and the same as when it was first tuned.
Why are you changing the plugs anyway. It seems that LT-1 EFI system is very good on plugs and they last a very long time. 60k and up I think. You might get zero performance gain from changing the plugs.
When I changed my plugs at 90k, I realized they were the originals from the factory!
Why are you changing the plugs anyway. It seems that LT-1 EFI system is very good on plugs and they last a very long time. 60k and up I think. You might get zero performance gain from changing the plugs.
When I changed my plugs at 90k, I realized they were the originals from the factory!
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You got more than 60,000 miles on your car? If so, I'd replace the ignition wires, looms, and holders, too. The O.E.M. ones get brittle from the engine heat and crack when you go to remove 'em.
Do one wire at a time so you don't get anything cross-wired. The O.E.M. Packard wires are numbered, though, so you can reference the firing order with the underhood label if you don't have your Factory Service Manual (FSM).
Don't forget the anti-seize compound for those aluminum heads, too.
Do one wire at a time so you don't get anything cross-wired. The O.E.M. Packard wires are numbered, though, so you can reference the firing order with the underhood label if you don't have your Factory Service Manual (FSM).
Don't forget the anti-seize compound for those aluminum heads, too.